Periodically poll a specified gpio pin on a Raspberry Pi and print when and what it changed to. Can specify pin, polling period, pin pull up/down, inverted output. A new instance will start by printing out current time and state. Periodically poll a specified GPIO input and output whenever a change has been noticed.\nEach time program starts, the current state is printed along with 'start'
The gpio-pollingd.sh is an example of an init.d script which runs gpio-polling as daemons on startup for various pins and outputs to a timestamped file for that instance.
Had tried using interupts driven by a Schmitt trigger but was still getting false readings so ended up using polling method. Setup with current sensor clamp on a wire running to hot water heater and used a comparitor and a Schmitt trigger buffer to sense when the thermostat turned on and off.
For usage instructions, check head of gpio-polling.py.